coverity: build versal_net with SDEI support

Enabling SDEI_SUPPORT helps to compile and analyze the following file:
    - plat/xilinx/versal_net/versal_net_sdei.c

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: Ica5c38e4d98a70fc4788032e848b9631fd7a4df5
1 file changed